k,(x + 1) + (x + 2) + (x + 3) + .... + (x + 100) = 5750
=> 100x + (1 + 2 + 3 + ... + 100) = 5750
=> 100x + 5050 = 5750
=> 100x = 5750 - 5050
=> 100x = 700
=> x = 700 : 100
=> x = 7
i,92.4 - 27 = (x + 350) : x + 315
=> 1 + 350 : x + 315 = 341
=> 350 : x = 341 - 316 = 25
-> x = 350: 25 = 14
h,720 : (41 - (2 x - 51) = 23.5
=> 41 - (2 x -51) = 720 : 40 = 18
=> 2x = 41 - 18 + 51 = 74
=> x = 74 : 2 = 37
Toán lớp 6
g,3+2x-1 =24 - [42-(22-1)]
3+2x-1 =24 - [42-(4-1)
3+2x-1 =24 - [16-3]
3+2x-1 =24 - 13
3+2x-1 =11
2x-1 =11-3
2x-1 =8
2x-1 =23
x-1 =3
x= 3+1
x=4
e,2.3x=10.312+8.274
=>2.3x=10.312+8.312
=>2.3x=18.312
=>2.3x=2.32.312
=>2.3x=2.314
=>3x=314
=>x=14
vậy x=14
Ta thấy:QLC là 2.
=>SSH là:(99-1):2+1=50(số)
=>Tổng là:(1+99).50:2=2500
Ta có:2500=(x-2)2=502=(-50)2
=>x-2=50 hoặc x-2=-50
x=52 x=-48
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